The present invention generally relates to integrated circuits, and more particularly to fabricating semiconductor structures having gate contacts electrically isolated from source-drain regions.
Contacts may be formed in order to make electrical connections to a semiconductor device. Contacts to source-drain regions of the semiconductor device may be referred to as CA contacts. CA contacts may be distinguished from CB contacts which may form an electrical connection to the gate of a semiconductor structure. The source-drain regions may remain electrically insulated from the gate terminal in order to improve functionality of the semiconductor device. Additionally, a short circuit between the source-drain regions and the gate may damage the semiconductor device. CA and CB contacts may be formed in a contact hole etched in an interlevel dielectric (ILD) layer deposited over the semiconductor device, and therefore may be surrounded by the ILD layer. As a result of device scaling, CB contacts may be placed in increasingly close proximity to the source-drain regions, thus raising the possibilities of having a short circuit between the CB contact and an adjacent source-drain region.